I've made this dish many times since then, and I'm quite proud of it. It's simply, easy, fast, healthy, and delicious.
Pan needed: Large stir-frying pan, such as a wok or deep skillet.
Preparation: Chop up the potatoes. Press or crush the garlic, chop it up, and put it aside. Chop up the mushrooms into a small bowl.
Heat up the wok on about 2/3 heat, and don't add the oil until the wok is hot. Wait until you can flick a few drops of water into the bottom of the wok, and watch them sizzle instantly and evaporate in one to two seconds. Cover the bottom with about a quarter inch of olive oil, and wait one minute for the oil to heat up.
Fry the potatoes in the olive oil until they're lightly brown. Dump the can of hash on top of the potatoes, and mix them up for about three to five minutes until the hash is soft and cooking. Add the fresh spinach on top of that, and mix it all together. As you mix it over the course of a few minutes, the spinach will absorb the moisture and change from big and leafy to the damp, soggy consistency you see when it's cooked or boiled. The potatoes and hash will blend together. Add the mushrooms and garlic, and keep on mixing the entire dish together until the mushrooms are soft, cooked, and no longer dry.
Serve in a large bowl, or two smaller bowls if you're feeding two. (I like to add fresh ground pepper at this point, because I love pepper.) Add grated or crumbled feta cheese on top. Alternately instead of cheese, use sour cream or Greek yogurt as a topping. The end result is a nice hash dish with extra flavor, very filling…and, no doubt, more healthy than canned ingredients. (Traditionally a fried egg is served on top of corned beef hash, but this dish actually tastes better without it.)